F4

UnderVoltage

Allen-Bradley · PowerFlex 40 Adjustable Frequency AC Drive

What does F4 mean?

This fault is triggered when the incoming AC line voltage drops below the drive's acceptable operating range. This can be caused by a sustained low voltage condition or a momentary power sag. This is an Auto-Reset/Run type fault configurable with parameters A092 and A093.

Source: Allen-Bradley PowerFlex 40 Adjustable Frequency AC Drive
Open Manual (Page 17)